Decomposition of EMI Noise into Common and Differential Modes in PWM Inverter Drive System

In this paper [20] an analytical approach to decomposition of total phase EMI noises through algebraic calculations and the Fourier transform has been presented. Separating conducted EMI noise into different, common and differential mode (CM and DM) HF current components is important for a proper spectral analysis and application of EMI mitigation techniques. The results of calculations have been compared to EMI currents measured on the motor side of the PWM drive system. The proposed approach can be useful in comparative analysis of the influence of inverter control algorithms on spectra of CM currents in a given drive system.